Baoqing Sun

Non‐smoking‐related chronic obstructive pulmonary disease: A neglected entity?

Chronic obstructive pulmonary disease (COPD) is an increasing cause of morbidity and mortality worldwide, and it has been strongly correlated to tobacco smoking. While a number of studies have concentrated on smokers only, recent published data demonstrate that at least one fourth of patients with COPD are non‐smokers, and that the burden of COPD in non‐smokers is also higher than previously believed. Risk factors of COPD in non‐smokers may include genetic factors, long‐standing asthma, outdoor air pollution (from traffic and other sources), environmental smoke exposure (ETS), biomass smoke, occupational exposure, diet, recurrent respiratory infection in early childhood, tuberculosis and so on. In Asian region, indoor/outdoor air pollution and poor socioeconomic status may play important roles in the pathogenesis of non‐smoking‐related COPD. The prevalence of COPD among never smokers varies widely across nations. Such a variation may arise from several aspects, including study design, definition of COPD, diagnostic criteria, age and gender distribution of the studied population, local risk factors and socioeconomic status. More investigations and efforts are required to elucidate the involved factors and their shared contributions to non‐smoking‐related COPD so as to achieve better estimation and reduction of the burden of this neglected entity worldwide.

Prevalence of allergen sensitization among patients with allergic diseases in Guangzhou, Southern China: a four-year observational study

BackgroundThe distribution of allergens may vary with different geographic areas, suggesting the importance of local epidemiological data to support evidence-based prevention and management of allergic diseases. We investigated the distribution of common allergens in allergic patients in Guangzhou, southern China.Methods7,047 patients with allergic symptoms were examined for serum sIgE to 15 common allergens in this region, based on the protocol of reversed enzyme allergosorbent test.Results4,869 (69.09%) of the subjects tested positive for sIgE to at least one of the 15 common allergens. There was no statistical difference in the overall rate of positive sIgE detection between males (3128/4523, 69.16%) and females (1741/2524, 68.98%). Der pteronyssinus and Der farinae were the most common aeroallergens, while eggs and cow’s milk the most common food allergens, responsible for higher positive rates of sIgE responses. A good correlation in positive sIgE response was found between Der pteronyssinus and Der farinae. By age-group analysis, we noted several peaks of sensitization to certain allergens: Der pteronyssinus, Der farinae, and Blomiatropicalis at age between 9 and 12; Blattellagermanica and mosquito at age between 15 and 18, cow’s milk before age 3; eggs and flour at age between 3 and 6; crabs and shrimps at age between 12 and 15. Along with older age, there was an ascending tendency in the overall positive rate of sIgE response to house dust mites among subjects who tested positive for sIgE to eggs or cow’s milk.ConclusionsDer pteronyssinus, Der farinae, cow’s milk, and eggs are major allergens in Guangzhou. Sensitization to eggs and cow’s milk is more common at younger age, and then gives place to the increasing prevalence of sensitization to Der pteronyssinus and Der farinae at older age. Such a sequence of events may be a result of allergy march. Knowledge on the prevalence of allergen sensitization in different age groups would help early diagnosis and intervention of allergic diseases in this large geographical region.

Local atopy is more relevant than serum sIgE in reflecting allergy in childhood adenotonsillar hypertrophy.

There was a lack of convincing evidence supporting the influence of allergy on the adenotonsillar hypertrophy (ATH). We investigated the presence of specific IgE (sIgE) in the serum and adenotonsillar tissues in children with ATH.

Co-Sensitization to Silkworm Moth (Bombyx mori) and 9 Inhalant Allergens among Allergic Patients in Guangzhou, Southern China

Objectives This study aimed to investigate the profile of sensitization to silkworm moth (Bombyx mori) and other 9 common inhalant allergens among patients with allergic diseases in southern China. Methods A total of 175 patients were tested for serum sIgE against silkworm moth in addition to combinations of other allergens: Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis, Blattella germanica, Periplaneta americana, cat dander, dog dander, Aspergillus fumigatus and Artemisia vulgaris by using the ImmunoCAP system. Correlation between sensitization to silkworm moth and to the other allergens was analyzed. Results Of the 175 serum samples tested, 86 (49.14%) were positive for silkworm moth sIgE. With high concordance rates, these silkworm moth sensitized patients were concomitantly sensitized to Dermatophagoides pteronyssinus (94.34%), Dermatophagoides farinae (86.57%), Blomia tropicalis (93.33%), Blattella germanica (96.08%), and Periplaneta americana (79.41%). Moreover, there was a correlation in serum sIgE level between silkworm moth and Dermatophagoides pteronyssinus (r = 0.518), Dermatophagoides farinae (r = 0.702), Blomia tropicalis (r = 0.701), Blattella germanica (r = 0.878), and Periplaneta americana (r = 0.531) among patients co-sensitized to silkworm moth and each of these five allergens. Conclusion In southern Chinese patients with allergic diseases, we showed a high prevalence of sensitization to silkworm moth, and a co-sensitization between silkworm moth and other five common inhalant allergens. Further serum inhibition studies are warranted to verify whether cross-reactivity exists among these allergens.

Food allergy and related risk factors in 2540 preschool children: an epidemiological survey in Guangdong Province, southern China

BackgroundAlthough the number of studies on allergic diseases in the general population of southern China is increasing, only a few have addressed food allergy (FA) in children in this region. The present study aimed to investigate the prevalence, clinical manifestations, spectrum of allergens, and related risk factors of FA in preschool children in Guangdong Province, southern China.MethodsA random cluster-sampling method was used to select 24 kindergartens from 12 cities in Guangdong Province. The parents or guardians of the children were requested to complete a questionnaire on general information and data regarding FA diagnosis and symptoms in the children and their first-degree relatives. Thereafter, the Chi-square test, multivariate regression analysis, and Spearman’s rank-order correlation coefficient analysis were performed to identify statistically significant differences.ResultsAnalysis of 2540 valid questionnaires revealed an FA prevalence rate of 4%. Adverse food reactions were due to the consumption of shrimp (4.4%), crab (3.2%), mango (2.3%), cow’s milk and dairy products (1.9%), and eggs (1.4%). Logistic regression analysis indicated that a history of FA and a history of allergic rhinitis in the first-degree relatives were the major factors leading to FA in children.ConclusionsThe incidence of FA in children in Guangdong Province is higher than that commonly believed. An individual’s genetic background is an important risk factor for FA. Hence, mitigation of the impact of lifestyle and environmental factors should be carefully considered to reduce the incidence of childhood FA.

Major grass pollen allergens and components detected in a southern Chinese cohort of patients with allergic rhinitis and/or asthma.

There is so far a paucity of data about allergen component-resolved diagnosis, and the prevalence of grass pollen allergen components in China, in contrast to those from western countries. Even in this country, allergies to grass pollen allergen components in the vast south are inadequately described. This study aimed to determine the major sensitizing grass pollens in Guangzhou, the largest city in Guangdong province of southern China. Included in this study were 258 patients having allergic rhinitis with or without asthma and 88 healthy controls. ImmunoCap100 was used to examine the serum samples for sIgE to Bermuda, Timothy, and Humulus scandens. Subjects who tested positive were further examined for sIgE to Bermuda antigen Cyn d 1, Timothy antigens Phl p 1/4/5/6/7/11/12, and CCD. The relationship of grass pollen allergy to specific antigen sensitization was assessed. As a result, 22.5% of patients with allergic rhinitis and/or asthma were positive for Bermuda-sIgE, 13.6% for Timothy-sIgE, and 7.0% for Humulus scandens-sIgE. These patients were more likely to be sensitized compared with controls (P<0.001). Of the Bermuda-sIgE positive patients, 53.4% were Cyn d 1 positive and 60.3% were Timothy-sIgE positive. Of the Timothy positive patients, 100% were positive for Phl p 4, 17.1% were positive for Phl p 1 and 8.6% tested positive for Phl p 5/6/7/11/12. Patients with high Bermuda-sIgE levels were more likely to be positive for other grasses. In 41.4% of Bermuda grass positive patients, CCD-sIgE was also positive. Sensitization to Phl p 4 was significantly correlated with CCD (rs=0.928).In summary, we found that these southern Chinese patients with allergic rhinitis and/or asthma tested positive for Bermuda, Timothy, and Humulus scandens IgE. A high Bermuda-sIgE level may predict sensitization to other grasses. Correlations between sensitization to CCD and grass pollen allergens suggested a likelihood of cross-reactivity. Further in vitro inhibition assays are required to confirm this relationship.

Reference Values of Induced Sputum Cytology in Healthy Children in Guangzhou, Southern China

OBJECTIVE: To establish normal reference values of induced sputum cytology in healthy children in southern China. METHODS: During a period from January 2010 to December 2011, a total of 580 healthy children (5–16 years of age) were approached. A total of 266 children (137 boys and 129 girls) participated in the study. Sputum induction was carried out by using 5% hypertonic saline. Cell types in the sputum were examined by using routine methods. RESULTS: Sputum induction was completed in 175 of the 266 subjects (65.79%), but 16 sputum samples were disqualified. The overall success rate was 59.77% (159/266). Macrophages and neutrophils were the predominant cell types: macrophages: median, 76.14%; interquartile range (IQR), 32.68%; and 2.5% to 97.5% percentile, 1.00% to 94.50%; neutrophils: median, 20.67%; IQR, 33.0%; and 2.5% to 97.5% percentile, 4.00% to 92.75%; eosinophils: median, 0.39%; IQR, 1.93%; and 2.5% to 97.5% percentile, 0.00% to 6.50%; and lymphocytes: median, 1.22%; IQR, 2.04%; and 2.5% to 97.5% percentile, 0.00% to 5.00%. The cell types did not differ among different age, gender, and passive smoking groups. Adverse events occurred in 4.4% (7/159) of the participants who completed the procedures but required no specific treatment to dissipate. Peak expiratory flow did not differ between those who completed the procedures compared with those who did not, suggesting that the procedure is safe and feasible in children. CONCLUSIONS: The current study represents the first attempt to develop normal reference values of induced sputum cytology in Chinese children, and could be used as a control for future studies.

A Component-resolved Diagnostic Approach for a Study on Grass Pollen Allergens in Chinese Southerners with Allergic Rhinitis and/or Asthma

Sensitization to grass pollen imposes a global risk for allergic airway diseases. Although prevention relies on local investigation of the pollen allergens, data on this topic are limited in southern China. Any available data were obtained by self-report questionnaires, skin prick tests, and total or specific IgE tests using crude extracts. For many reasons, these methods are unreliable. Serum sIgE reactivity to Bermuda grass, Timothy grass, and Humulus scandens allergens in a cohort of patients from Greater Guangzhou (southern Chinas largest city and its outskirts) with allergic rhinitis and/or asthma were examined using a fully-automated immunoassay analyzer as a component-resolved diagnostics (CRD) tool. For the first time, a considerably high prevalence of Bermuda grass sIgE positivity was demonstrated in Chinese southerners with allergic rhinitis and/or asthma. In these patients, a subtle prevalence of sensitization to Timothy grass and Humulus scandens was also noted, which may arise from cross-reactivity, as the latter two are not common in the region. This was also supported by the detection of allergen components. Fully-automated immunoassay analyzers may offer satisfactory consistency between regions, laboratories, and institutions and over time. The automaticity of the instrument may enable a standardized detection that would not have been readily revealed before the advent of CRD. This is a study that uses a CRD approach to investigate sensitization to grass pollen allergens in southern China. It adds to current evidence in the literature. Future studies are needed to validate these findings. However, although CRD is a useful tool, the findings made with the fully-automated immunoassay analyzer should not substitute for other laboratory investigations, clinical evaluations, and physician expertise.

Comparative Analysis of Serum Allergen sIgE Detected by Western Blotting and Fluorescent Enzyme Immunoassay

BACKGROUND Various new methods to diagnose allergens have gradually developed in recent years. The present study aimed to evaluate the diagnostic performance and clinical utility of Allergy-Q detection system (Proteometech Inc., Korea) on serum allergen-specific IgE (sIgE). METHODS Immunoblotting (Allergy-Q system) and fluorescent enzyme immunoassay (ImmunoCAP system, Phadia Inc., Sweden) were used to detect serum total IgE and allergen sIgE of 244 cases of allergic diseases, followed by comparative analysis of the results. The study focused on analyzing 15 kinds of common allergens. RESULTS Comparison of the two methods showed that the diagnostic performance of qualitative results of AllergyQ system for the majority of allergens was satisfactory, with Dermatophagoides farinae having the highest agreement (96.4%) and sensitivity (97.8%) and Dermatophagoides pteronyssinus having the highest specificity (100%), positive predictive value (100%), and Youdens index (J = 0.951). Scatter plots and Spearmans correlation analysis showed correlations between the quantitative results of the two methods, with the highest correlation for Dermatophagoides pteronyssinus (r = 0.875, p < 0.001). CONCLUSIONS For most common allergens, the Allergy-Q system is an effective method for diagnosis. It is safe, convenient, economical, accurate, and efficient in screening multi-allergens. Moreover, it is good for semi-quantitative detection of allergens in the basic hospitals that are unable to carry out the ImmunoCAP detection, and also for patients with fewer samples. However, its clinical application needs to be validated using a number of samples from a variety of countries and regions.

Diagnostic value of KL-6 in idiopathic interstitial pneumonia

Background Idiopathic interstitial pneumonia (IIP) can induce type II alveolar epithelial cell proliferation and pulmonary basement membrane damage and subsequent release of Krebs von den Lungen-6 antigen (KL-6) to the bloodstream. This study investigated the diagnostic and prognostic value of serum KL-6 levels for IIP. Methods One hundred five patients with lung disease were divided into IIP (n=75) and non-IIP groups (n=30) according to pathological and computed tomography findings. Serum KL-6 levels were evaluated in blood samples from all subjects. Nineteen IIP group patients were also subjected to a longitudinal study of disease progression and serum KL-6 levels over time. Results Serum KL-6 levels were significantly higher in the IIP group vs. the non-IIP group [1,096.0 (565.0-1,544.0) vs. 226.0 (173.5-346.5) U/mL; P<0.01]. Within the IIP group, serum KL-6 levels differed significantly between patients with and without concomitant disease or pulmonary infection (Z=-2.475, P=0.013). In a receiver operating characteristic (ROC) curve analysis, the area below the curve for serum KL-6 was 0.911 [95% confidence interval (CI): 0.847-0.975, P<0.001], indicating a good diagnostic performance for IIP, with a cut-off level of 485 U/mL, sensitivity of 85.33%, specificity of 90.00%, positive predictive value (PPV) of 95.52%, negative predictive value (NPV) of 71.05%, and Kappa value of 0.70. Accordingly, the serum KL-6 and clinical diagnostic results were consistent. Moreover, in the longitudinal study, the serum KL-6 levels differed significantly from before to after treatment in patients with exacerbated or improved disease (P=0.004 and P=0.043, respectively), whereas no obvious changes were observed in patients with stable disease (P=0.692). Conclusions The serum KL-6 level is a valuable and significant diagnostic marker of IIP and a useful predictor of clinical prognosis.